This relates generally to electronic devices with displays, and, more particularly, to organic light-emitting diode displays.
Electronic devices often include displays. Displays such as organic light-emitting diode displays have pixels with light-emitting diodes. The light emitting diodes each have an anode and a cathode. Emissive material is interposed between the anode and cathode. During operation, current passes between the anode and the cathode through the emissive material, generating light.
The anodes in an organic light-emitting diode display are formed from a photolithographically patterned layer of metal. Unlike other metal structures in a display such as signal lines that may be covered with opaque masking material, the anodes are exposed. The anodes may therefore give rise to strong specular light reflections. This may cause ambient light to be reflected towards a viewer. These reflections can make it difficult to view images on the display. Ambient light reflections may be suppressed by covering a display with a circular polarizer, but use of a circular polarizer can significantly reduce light emission efficiency.
It would therefore be desirable to be able to provide organic light-emitting diode displays with enhanced light emission efficiency.